Mechanochemical Strategies for the Preparation of SiO2-Supported AgAu Nanoalloy Catalysts

Rafael T P da Silva; Susana I Córdoba De Torresi; Paulo F M de Oliveira

doi:10.3389/fchem.2022.836597

Mechanochemical Strategies for the Preparation of SiO₂-Supported AgAu Nanoalloy Catalysts

Front Chem. 2022 Feb 2:10:836597. doi: 10.3389/fchem.2022.836597. eCollection 2022.

Authors

Rafael T P da Silva¹, Susana I Córdoba De Torresi¹, Paulo F M de Oliveira¹

Affiliation

¹ Institute of Chemistry, University of São Paulo - USP, São Paulo, Brazil.

Abstract

Silver-gold nanoalloys were prepared from their metal salts precursors through bottom-up mechanochemical synthesis, using one-pot or galvanic replacement reaction strategies. The nanostructures were prepared over amorphous SiO₂ as an inert supporting material, facilitating their stabilization without the use of any stabilizing agent. The nanomaterials were extensively characterized, confirming the formation of the bimetallic nanostructures. The nanoalloys were tested as catalysts in the hydrogenation of 2-nitroaniline and exhibited up to 4-fold the rate constant and up to 37% increased conversion compared to the respective single metal nanoparticles. Our approach is advantageous to produce nanoparticles with clean surfaces with available catalytic sites, directly in the solid-state and in an environmentally friendly manner.

Keywords: ball-milling; bimetallic nanoparticle; bottom-up approach; galvanic replacement reaction; mechanochemical synthesis; nanoalloys; nanocatalysis; nitrobenzene reduction.